Electrically operated system



Oct. 22, 193 s. w. HETHERHNGTON ELECTRIGALLY OPERATED SYSTEM Filed Nov. 6, 1928 5 Sheets-Sheet l IN VENT OR Oct. 22, 1935.

s. w. HETHERINGTON 17,968

ELECTRICALLY OPERATED SYSTEM Filed Nov. 6, 1929 5 Sheets-Sheet 2 152 r I I 2 w: INVENTOR WWQ aw ATTORNEY @cfca 22;, W35. s. WQHETHERINGTON 299179953 ELECTRI CALLY OPERATED SYSTEM Filed Nov. 6, 1929 5 Sheets-Sheet 5 v v 3 r I INVEIYTCR L J W 1A) W ATTORNEY O 9 1935- s. w. HYETHER'INGTYON 2,917,968

ELECTRICALLY OPERATED SYSTEM Filed Nov. 6, 1929 5 Sheets-Sheet 4 v INVENTOR W mu ATTORNEY y 193$ s. w. HETHERINGTON ELECTRICALLY OPERATED SYSTEM 5 Sheets-Sheet 5 Filed Nov. 6, 1929 A 270mm Patented Oct. 22, 1935 UNITED STATES PATENT OFFICE Sidney W. Hetherington, Piqua, Ohio, assignor to Delco-Light Company, Dayton, Ohio, a corporation of Delaware Application November 6, 1929, Serial No. 405,258

8 Claims.

This invention relates to electrical apparatus and also to that type of apparatus or system which contains a fluid under pressure and more particularly to the automatic control thereof.

An object of this invention is to provide a system utilizing a fluid under pressure having means, which may be electrically operated, for maintaining said fluid under predetermined pressure or capacity limits in at least part of said system.

Another object of this invention is to provide a' carburetor for furnishing carbureted air suitable for household use under pressure, and hav-- ing means, which may be electrically operated, for maintaining said carbureted air within the H carburetor under predetermined pressure limits.

A further object is to provide a pressure responsive switch for controlling a system utilizing a fluid under pressure, and having electrically operated means for maintaining said fluid under predetermined pressure limits, and to arrange said switch for preventing the operation of the electrically operated means under abnormal pressure conditions.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a side elevation of a system or carburetor embodying features of this invention;

Fig. 2 is an enlarged cross sectional view of a portion of the apparatus shown in Fig. 1;

Fig. 3 is a top plan view of a portion of the apparatus shown in Fig. 2;

Fig. 4 is an enlarged view taken from the rear of Fig. 2;

Fig. 5 is a front plan view of a pressure responsive switch embodying features of the present invention; and

Fig. 6 is a view taken along the line- 6-6 of Fig. 5.

This invention may be embodied in a system 26 utilizing a fluid under pressure and includes means 2] for maintaining said fluid under predetermined pressure or capacity limits in at least part of said system as will be noted in the drawings. The means 2| for maintaining said fluid under predetermined pressure limits within the system may include an electrically driven compressor 24 which may be driven by an electric motor 25 drivingly connected to the compressor 24 for instance by a belt 21. The means 2| for maintaining said fluid under predetermined pressure or capacity limits within the system also includes a pressure or capacity responsive switch connected to the system for instance near the means 2|. The pressure responsive switch 30 includes a pressure or capacity responsive movable or expansible element 32 and movable con- 5 trol means 34 operatively connected to the element 32 for controlling the operation of the electrically driven compressor 24.

The system may be a carburetor as shown in Fig. 1. When the system is a carburetor, a quanl0 tity of high grade gasoline may be introduced into a tank 35 for instance through a feed pipe 36. Air in the form of a stream may be contacted with the gasoline within the tank 35. The stream of air may be produced by means of a perforated 15 pipe placed near the bottom of the tank 35. The air, laden with the proper amount of hydrocarbons, may be withdrawn through the pipe 4|, and may have its pressure reduced, if necessary, by means of an automatic pressure reducing 20 valve 43, which discharges the carbureted air at the substantially constant pressure through pipe leading to suitable appliances such as household gas stoves having the usual type of burners used with this type of apparatus, water heaters, 25 small industrial gas burners or the like. For ordinary household use, the gas in the pipe 45 may be maintained at a substantially constant pressure of 4 oz. by means of the pressure reducer or regulator 43. 30

Air may be supplied to the pipe 40 at a substantially constant pressure by any suitable mechanism, for instance, the means 2| may be used. It may comprise the compressor 24 which may have a connection with the pipe 42 which 35 connection includes an air tank 49, an oil separator and a pipe connection 5|, The oil separator 50 may, if desired, be connected to a sight feed oil dropper 52 feeding oil into the inlet 53 of the air compressor 24. 24 may have its inlet 53 extended as shown at 54 through the wall 55 forming the outside of the building in which the means 2| is located. Preferably the tank 35 may also be placed outside of the building, which is to be supplied with 45 gas. Also if desired the tank 35 may be buried underground, and may be provided with a liquid inlet connection 36 leading to the top of the ground and if desired, a liquid level gauge may be placed in the connection 36. Either the pipe 50 4| or the pipe 45 may be laid into the building which is to be supplied with gas.

The compressor 24 may be of the rotary compressor type having rotating vanes 60. The compressor may discharge through a pipe 6 leading to The air compressor v the oil separator 50. The separator may be provided with baffles 62 and with an outlet 64 connected to a pipe 65 leading below the level of a body of lubricating oil I9 in the air tank '49.. The pipe 5I is connected to the air tank 49 above the level of the oil I0 and the other end connected to the pipe 40. Preferably a check valve II is provided which permits the air to flow into the tank 35 but prevents return thereof. A suitable check valve I2 may be provided which permits an upward flow through the passage 13 but which falls into place and prevents a downward flow. Should there be a slight leakage in the check valve I2, the lubricating oil I0 would be forced up through the pipe 65 and outlet 64 and would form a liquid seal above the check valve I2. The liquid seal would be far more effective than a gas seal, so that the slight air leak would be eiiectually stopped.

The compressor 24 may be operated so as to maintain a substantially constant pressure or capacity somewhere within the system, for instance, within the tanlr 49. Thus the pressure switch 30 may be connected by means of a pipe I5 with a connection IB leading somewhere within the system, for instance, to the tank 49. The switch may be responsive to pressure or capacity within the system or tank 45 and may be set so as to start and stop the motor 25 through the electrical conduit TI in response. to constant pressure or capacity limits within the system or tank 49. Preferably these limits, when they are pressure limits, are two pounds when the motor starts and an upper limit of seven pounds when the motor stops. The pressure switch also includes an emergency limit or low pressure cut-out position so that if the pressure within the tank 49 falls below the low pressure limit, in this case two pounds, the switch will render the electrically driven compressor 24 inoperative and in so doing will assume a position whereby the compressor will not be rendered operative until a manual reset 89 is actuated to cause the switch to assume the normal low operating pressure limit or closed circuit position.

Referring to Figures 5 and 6, the pressure responsive switch 39 includes the control means 34 operatively connected to the pressure respons'ive expansible element or sylphon 32 by actuating mechanism comprising, a lever and an arm 86. The lever 85 is pivotally mounted on a housing 88 for the switch 30 at 89. The lever is operatively connected to the expansible element 32 between a pointed portion 90 of a screw threaded member 9| connected to the expansible element 32, and a pointed portion 94 of a spring mechanism 95. The screw threaded member 9| of the sylphon 32 is surrounded by a spring 96. The spring 96 is carried by a cup-shaped member 91 and is clamped between a lower portion 98 of the cup-shaped member and an adjustable nut 99.- The spring mechanism includes a disc IOI which includes the pointed portion 94, A spring I03 is clamped between the disc IOI and an adjustable screw threaded disc I05 carried by a screw threaded member In! secured to the housing 88. By a proper adjustment of the nut 99 and the disc I95 the tension of the springs 95 and I03 will be such that the expansion and contraction of the sylphon 32 will be regulated so as to give a proper movement to the lever 85 to control the control means 34 in response to certain pressures within the carburetor to thereby maintain predetermined pressure limits within the system or carburetor.

The armfifi pivotally connected to the lever '35 at Ilfiand is pivotally connected to a movable member I I I of the control means 34, which moveduit TI and forming a circuit for controlling the operation of the electrically driven compressor.

As previously described the control means 34 may assume any one of three positions namely, an upper limit or high pressure cut-out, a lower limit or closed circuit position and an emergency or low pressure cut-out position. When the compressor is operating and the pressure within the system attains a predetermined high value, in this case seven pounds, the expansible element 32 will cause the upward movement of the screw threaded member 9I to move the lever 85 upwardly to assume the position approximately as indicated at i3il. This movement causes the arm 86 to pivot the tube II'6 to thereby assume the position indicated at I3I. Thus the mercury drop I29 will be subjected to a swinging movement so that at least one of the contacts will be free therefrom to change the operation of the compressor 24, that is, in the present instance, in the preferred embodiment to interrupt the electrical circuit to change the operation of the compressor, for instance, to the stopped condition.

As the pressure within the system or carburetor recedes to two pounds, ror instance, the expansible element 32 will cause the downward movement of the screw threaded member 9| to cause the lever 85 to pivot the control means 34 to assume the low pressure starting or closed circuit position, which position is indicated at I31. When the control means 34 assumes the low pressure starting or closed circuit position, the mercury drop I 20 will complete a circuit between the contacts I2I and M2 to change the operation of the compressor, for instance, to the running condition, which operation will ordinarily continue until the high pressure cut-out position has.

been attained as previously described.

In the event there is a failure to receive a current supply for the motor 25 and the pressure within the system or carburetor should recede to a point below the low pressure starting position, for instance below two pounds pressure, the contraction of the expansible element 32 will cause the lever 85 to assume the position approximately at idzl to thereby cause the control means 3 to pivot to thus assume the low pressure cutout position which is indicated at I4I. This movement of the control means 34 will cause the mercury drop I29 to become separated from at least one of the contacts to change the operation of the compressor.

When the current supply has been resumed, the pressure within the system will of course be insufficient to cause the control means 34 to assume low pressure starting or closed circuit position. Thus the manual reset 39 has been provided. The manual reset 89 may be used for moving the lever from low pressure cut-out position to low pressure starting or closed circuit position to thereby cause the control means 34 to render the system operative.

Thus it is to be seen that the compressor 24 has its operation intermittedly changed. During the running period, the space I50 in the separator 50 is substantially at the same pressure as tank 49. That is, it is at superatmospheric pressure. The superatmospheric pressure forces oil from the bottom of the separator up through the pipe I5I connected to a pipe I52 leading to the sight feed oil dropper 52, which may be provided with a suitable adjustable needle I54. Thus during the running period of the compressor 24, oil is fed into the inlet 53, but during the period of idleness of the compressor 24, the pressure in the space drops substantially to atmospheric pressure because of air leakage in the compressor 24 and no oil is forced through pipes I5I and I52 into the oil dropper. If desired the separator may also be provided with an oil gauge rod I60 which may be connected to the threaded plug I 6| engaged with the casing of the separator. This rod I60 may be removed in order to determine the oil level in the separator 50, by inspection of the oil covered portion of the rod I60.

From the foregoing description it will be noted that there has been provided a system 20 utilizing a fluid under pressure and having means 2I, which may be electrically driven, for maintaining said fluid under predetermined pressure limits in at least part of the system. It will also be noted that said means 2| may include the electrically driven compressor 24 and the pressure responsive switch 30 for controlling the operation of the electrically driven compressor 24, and said switch may be arranged in such a manner so as to change the operation of the compressor by a movement of the expansible element 32 in either direction from the operating position. Thus it will be noted that the pressure responsive switch prevents the operation of the electrically driven compressor under abnormal pressure conditions.

Where electric current is not available, the means may be replaced by some other type of driving mechanism for the compressor, and the control device may be modified so as to control the other type of driving mechanism.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A pumping system comprising a pump, a motor for driving said pump, a single switch for automatically maintaining the operation of said pump between predetermined low and high fluid pressure limits respectively, said switch having incorporated therein pressure responsive means apart from the pump for preventing the operation of said pump whenever the fluid pressure of said system reaches a predetermined pressure limit beyond said first named limits until said switch is manually reset.

2. A fluid pressure system comprising a driven member for altering conditions in said system, a motor for driving said member, a single switch connected in the system beyond the pump for automatically maintaining the operation of said driven member to maintain said system within predetermined pressure limits, said switch having incorporated therein means for preventing the operation of said driven member whenever the pressure in said system reaches a predetermined limit beyond said first named limits until said switch is manually reset.

3. A pumping system comprising a pump, a motor for driving said pump, a single switch for automatically maintaining the operation of said pump between predetermined low and high fluid pressure limits respectively, said switch having incorporated therein means for preventing the operation of said pump whenever the fluid pres- 5 sure of said system reaches a predetermined pressure limit beyond said first named limits until said switch is manually reset, said switch including a mercury drop and contacts intermittently bridged by said drop. 10

4. A fluid system comprising a driven member for altering conditions in said system, a motor for driving said member, a single switch for automatically maintaining the operation of said driven member to maintain said system within 16 predetermined pressure limits, said switch having incorporated therein means for preventing the operation of said driven member whenever the pressure in said system reaches a predetermined limit beyond said first named limits until 20 said switch is manually reset, said switch including a mercury drop and contacts intermittently bridged by said drop.

5. A fluid pressure system comprising a driven member for altering conditions in said system, 25 a motor for driving said member, a single switch for automatically maintaining the operation of said driven member to maintain said system within predetermined pressure limits, said switch having incorporated therein means for prevent- 30 ing the operation of said driven member whenever the pressure in said system reaches a predetermined limit beyond said first named limits until said switch is manually reset, said switch including a bent tube with contacts at the elbow 35 of said tube and a mercury drop in said tube bridging said contacts.

6. In combination with a member to be controlled by fluid pressure under predetermined conditions, a single switch for controlling said 40 member, said switch intermittently operating to open and close in response to said conditions, said switch having incorporated therein means for preventing said intermittent operation whenever the conditions reach a predetermined limit 45 beyond said first named limits until said switch is manually reset.

7. In combination with a member to be controlled by fluid pressure under predetermined conditions, a single switch for controlling said 50 member, said switch intermittently operating to open and close in response to said conditions, said switch having incorporated therein means for preventing said intermittent operation whenever the conditions reach a predetermined limit beyond said first named limits until said switch is manually reset, said switch including a mercury drop and contacts intermittently bridged by said drop.

8. A pumping system comprising a fluid con- 60 tainer, a pump for altering the mass of the fluid contents of said container, a motor for driving said pump, a single switch for automatically controlling the starting and stopping of said motor and pump to maintain the mass of the fluid contents of said container between predetermined low and high limits, said switch having incorporated therein means for preventing the operation of said pump whenever the mass of the fluid contents of said container reaches a pre- 70 determined limit below said predetermined low limit until said switch is manually reset.

SIDNEY W. HETHERINGTON. 

